The goal of this proposal is to acquire a spinning-disc confocal microscope equipped for FRAP and photoactivation to be used for the measurement of dynamic processes in live cells. The major and minor users of this instrument are in the Departments of Biochemistry and Biological Sciences at Dartmouth Medical School and College. Their research projects are aimed at understanding molecular mechanisms of fundamental cellular processes such as chromosome segregation, actin organization, nuclear transport, and membrane trafficking. Satisfactory completion of the stated goals of the NIH-sponsored projects of these users requires examination of dynamic cellular processes in live cells with high spatial and temporal resolution and minimal phototoxicity. The spinning-disc confocal microscope described in this proposal is a state of the art instrument that satisfies these needs by using proven technology (Yokogawa spinning-disc confocal head;Nikon inverted microscope;Photonic Instruments photobleaching/activating laser;Improvision software) to provide real-time confocality (high spatial resolution) at rapid rates (high temporal resolution) with minimal light exposure. It would represent the only instrument of its kind to serve the entire Dartmouth life science community. PUBLIC HEALTH RELEVANCE: The goal of this proposal is to gain insight into the molecular mechanisms that underlie various human disease states such as tumor cell aneuploidy, metastasis, and membrane biology related to health issues such as insulin action in diabetes. The unique attributes of the microscope requested give the investigators unparalleled ability to observe dynamic processes in living cells, and insight into disease etiology can emerge from understanding the dynamics of these fundamental cell mechanisms.